Mold plug



April 5 1938. A ESTEP 2,113,445

MOLD PLUG Filed July 21, 1937 INVENTOR. ARTHUR 6- 575? ATTORNEYS Patented Apr. 5, 1938 anaus MOLD PLUG p, Waynesbuu, cre- Greer Firepr- Arthur C. Este The Whita Waynesbur Ohio, at I corporation of VENT: oi-"r ce;

Ohio, assignor'to oofing Company,

Ohio

Application July 21, 1937, Serial No. 154,801 7 Claims. (01. 22-139) This invention relates to improvements in inmore particularly to a commold e risk of non-metal- A further object'is ng yielding qualities lics getting into the ingot. to provide a mold plug havi 10 whereby to seat securely in the bottom hole of ingot mold plug constructed according to my 10- the ingot, which, withal, may be readily removed invention; I therefrom when the ingot is stripped from the Figure 2 is'a sectional/view taken online 2-2 mold, and which will satisfactorily prevent leakof Figurel; v 1 l v age of molten metal'past all or any substantial Figure 3 is a; transverse sectional view. with portion of the plug. A further object is to pro parts broken away showing an, ingot mold plug 1!- vide a plug resistant to the wash of the molten of my invention positioned in an steeland impervious to deleterious action of the out various of the out those functions and to coa related elements in-an adva further object is to provide a the mold and the i'orcib Acc tion '6 is pre of its large a blow receiving protecti tion of the plug to faci plug into the ingot mo objects relating to simp economies of m'anufa will appear from 'th the appended drawing Figure 1.-is a t the ingot cast ther I Figure 4' is a. transve modified form of mo ventlon;

F gure 5 is'a sectional ther modification v vention.

of the big-end-up type pouring of the ingot I.

structedthat thenonwill not float u invention illustrate truncated conical f substantially coext face of the mid-p0 the ingot mold. A. erably about 1'," plug is about;3"

the plug by such means l is preferably shaped at the plug in its entirety co ture having a metal top body in which both elem tal portion provides ve cap'qfor the clay porlitate the driving vof the id plug, opening. mother licityof construction and 5 cture and other advantages following description and in which: rans'verse sectional view of ,an

plug in which the me ingot mold with ein;

rsesectional view of a idv plug. embodying-my in- I go view illustrating a-furmold plug ofmy inby those skilled in the is employed to seal'the nd of an ingot mold I and that such plugs are opening H prior to the The opening the botof the will be up ly driven into the metallic p into the ingot. a ording to the preferred embodiment of myd in Figure 1 the'body poroi the plug P is made of burned clay and ferably made by extrusion in the direction axis and thereafter pressed or molded too.

am complementary to and 40 ensive with the conical aurrtion oi the conical hole' H in metallic plate or disk L 'preI- to thick, where the-whole V 7 deep, is secured to the tenor diameter surface of thebody portion o'i as a bolt 1. The plate its periphery I to conparts of the plug mprises a unitary strucface and a burned clay ents coast with the con- 66 ical surface of the hole H in the same way and offer mutual support and protection to each other.

I recognize that in commercial practice the conical exterior surface of the clay body portion will not be a true geometrical cone, nor will the conical wall of the hole H be a perfect geometrical cone, particularly after the mold has been in use for some time. One of the advantages of a refractory or burned clay mold plugis that it may be driven into thebottom hole'of the mold, and with a reasonable force may fracture a little about its exterior conical surface whereby to conform more perfectly to the adjacent wall of the hole and thereby more securely bear the weight of the whole ingot. Where the mold plug is entirely made of refractory material, the plug must be stout enough to'withstand the impact of being driven into the bottom hole, whereby to prevent bodily rupture thereof or spalling from the top surface thereof. These characteristics, however, are necessarily antagonistic to obtaining a desirable though limited fracture or yielding in the conical surface of the plug, and are thus antagonistic to obtaining a full bearing between the conical surfaces of the plug andthe wall of the bottom hole. One of the advantages of my invention is that Imay use a relatively soft clay portion adapted to yield enough to obtain a good or full bearing along its conical surface with the hole in the mold, because the impact of driving the plug into' place is widely distributed through the top plate 1, which is tightly secured thereto.

Those skilled in the art will understand how relative hardness or softness can be obtained in a burned clay product in its manufacture, and I note only by way of example that for similar burning times and temperatures the hardness is measurably increased when the plastic mass is well deaerated in the course of extrusion on the one hand, and that softness, as I employ the term, is materially increased where deaeration is reduced oreliminated, and also where finely divided carbonaceous material such as powdered -coal is mixed with the clay prior to extrusion.

and is burned out during the burning whereby to measurably increase the porosity of the ware.

Since, as I have indicated, I desire that the metal plate or disk 1 carry out all or substan-- tially all of the hydraulic scaling function in closing the bottom opening in the mold, I prefer that its peripheral edge have a sealing contact with the adjacent conical wall' of the hole H, but I also desire that the plate I be supported by the body portion i, whereby its mechanical function of supporting the-weightof the ingot will be substantially limited to compression'within its own thickness. In other words, I desire to avoid having the plate I take a load bearing engagement along its periphery whereby to tend to suspend the plug in the hole. One reason for the latter being that did the plate tend to suspend the plug,- then a much thicker and stronger plate would have to be provided, and one would thus revert back to a solid metallic plug with its disadvantages of cost and its relative incapacity to obtain a tight sealing fit in the hole.

It is convenient and economical to make -the plates 1 by punching or shearing them from the lower peripheral edge of the plate 1, that is the edge adjacent the top surface of the clay body portion 6, very nearly to the maximum diameter of the top surface of the body portion or a little smaller than that diameter in the order of about ,64 of an inch. In this manner, when the whole plug is rammed into the bottom hole of the mold, and the surface of the clay portion gives or is scratched away somewhat, then the lower edge of the periphery of the plate 1 contacts or ap proaches intimate contact with the wall oi; the hole H. The contact between the disk and the wall of the hole tending first to bev a circular .line, the metal of the disk tends to give a little under the impact with which the whole plug is driven into the hole, and because of the limited area of contact and the give of the metal, the disk per se does not tend to take all or any substantially great portion of the load to be sup ported, nor does it interfere with an ample load bearing engagement between the plug and the wall of, the hole. the plate 1 has no actual or complete contact with the wall of the hole, still the whole area of the non-metallic portion of the plug with which molten steel may contact is so small and so screened from the wash of the molten steel that the possible entrance of non-metallics into the ingot is substantially eliminated.

It will also be noted that the disk I is preferably secured tothe clay body- 6 of the plug in its central portion, whereby to permit a limited yield or give between its peripheral portion and g the peripheral part of the top surface of the clay v .of the ingot.

During the formation of the clay body of the plug an aperture 4 is provided centrally thereof to receive the bolt 8 and the lower end of the bolt receiving aperture is preferably enlarged as at 9 and is preferably given a square configuration to prevent the nut Ill from turning within the body I. The shank of the bolt immediately adjacent the head is preferably square according to carriage bolt construction and thus rotation of the disk I and bolt 8 relative to the nut III, while the latter is held in the non-circular hole 0, permits ready assembly of the parts and a firm union between them. The squared aperture 9 in addition to housing the nut lli provides a re-entrant portion to receive the head ll of a bolt of an adjacent plug upon stacking a series of mold plugs in shipping and storage.

During the pouring of the ingot the plate 1 receives the thermal shock of the molten metal and said plate 1 is preferably proportioned with regard to its thickness so that the heat of the molten metal will effecta welding as at W (in Fig. 3) of the plug to the ingot 3. As a specific example I have found that a plate I having a thickness of about fiths of an inch operates satisfactorily to effect a welding of the plug to the ingot and yet maintain its identity as a steel plate throughout thepour so as to keep the metal of the ingot 3 ,out of contact with the refractory material of the plug. Subsequent to the stripping of the ingot from the mold the mold plug serves as a stool or support for the ingot when the same is placed in the soaking pit. A mold plug constructed according to my invention thus not only eifectively prevents the loss of molten metal Even where the periphery of during the pouring and prevents the, floating of non-metallic particles within the ingot, but also maintains the finished ingot free of contact with the soaking pit liquid or other impurities on or adjacent the floor thereof.

Although as indicated above it is preferred to secure the plate I to the body of the plug 6 by a bolt I as shown in connection with the embodiplug 2i may be formed like the clay body 6 of the preferred form. Among the advantages of this is that the head of the bolt i9 is less subiected to the wash of the molten metal during the pouring of the ingot.

In Figure 5 I have shown a further modification, which is particularly feasible when the body portion l8 of the plug is made of relatively soft and workable refractory material such as porous burned clay in which powdered coal has been added to the wet mix (25% powdered coal to 75% powdered clay by weightbeing a workable percentage) and burned out during firing of the ware, whereby to leave the ware relatively soft and porous. Such ware is capable of receiving and holdinga lag screw IS without injury to the refractory poi'tion l6, particularly where a small tapered hole is formed in the refractory body when the same is pressed into its conical form, the tapered hole preferably being about the shape of the cone defined by the base of the threads in the lag screw. In this form of my invention the plate or disk I! coacts with the clay body portion ii in substantially the way hereinabove described with reference to the other forms of my invention. In this particular modification I prefer that the mid-portion of the disk I] be drawn downwardly as at i8, whereby to receive the head of the lag screw, keeping the top of it about flush with the top of the surface of the disk. The top surface of the clay body portion i6 is similarly indented to receive the depression or dimple i8 of the disk. In this manner the head of the screw is kept downwardly out of the wash of molten steel, and the finished and ."ourved interior bottom assembled plugs are readily stacked one upon another during shipping and storing. Moreover, in this form of my invention the molding of the wet extruded clay stock, in changing the initial cylindrical shape of the plug to the form of a truncated cone, is facilitated somewhat by the displacement of clay from the upper and central portion thereof outwardly in the direction of expansion of the plastic mass from its initial cylindrical diameter to its enlarged diameter at the larger end of the truncated cone.

Referring particularly to Figure 3, it will be observed that in all forms of my invention the plug P is preferably proportioned to enter the hole H, and be securely seated in that hole so that the whole upper and lower limits of the plug liewithin the upper and lower limits of the conical surface of the hole H. In this manner the plug lies somewhat above the bottom of the ingot mold I, whereby the plug engages the walls of the hole to the exclusion of the stool or other means disposed below the bottom of the mold. The top of the plug, including the metal disk, also ,lies within the conical wall of the hole, whereby to coact therewith as above described, and

"Jacent interior more particularly to be disposed below the adbottom walls 2 of the 'mold I, whereby to have its peripheral edges protected from the washof molten steel, and the plate is thus freed from the" tendency'of. the wash of the steel to separate it from the plug.

From the foregoing it will be seen that I have provided a plug having many advantages to be obtained in its operation and use; vthat the plug is simple in construction and lends itself to the economy of manufacture; that it guarantees a satisfactory seal of the bottom .hole of the ingot in a novel and advantageous way, and otherwise facilitates and expedites the casting of ingots and advances the art thereby. I

While I have indicated a perference for burned clay as the material for the bodyportion of my improved plugs, it should be understood that my invention may be advantageously practiced with other refractory or semi-refractory materials such as a mixture of slag and cement ordry pressed clay in the body portion of the plug.

Although I have illustrated and described certain specific forms in which my invention may be practiced, various changes and modifications will occur to those skilled in the art, all within the precepts of my invention, and I do not care may be entitled in view of the priorart.

I claim:-

hole and the peripheral surfaces of both the body and cap portions of said plug having operative engagement therewith.

2. In combination an ingot mold having a surface merging into a conical walled bottom hole, a metallic sealing plate disposed transversely of said hole having its peripheral edge in sealing relation to the conical wall of the hole, a refractory plug in said hole having load bearing engagement with the said conical wall of said hole directly below said sealing plate and supporting said plate and fixedly secured thereto.

3. An ingot mold plug having aburned clay body portion of truncated cone shape and a flat steel plate applied to the maximum diameter of and means to secure said plate to said body com- 75 prising a bolt having a non-circular shoulder beneath the head thereof to flt non-rotatively within said plate, and a nut disposed within said body having a threaded engagement with the shank of said bolt and held against rotation in said body.

5. The combination of an ingot mold having a tapered bottom hole, and a tapered plug with its tapered surface substantially coextensive with tapered surface of said hole, said plug comprising a load bearing refractory body portion, the points or limited areas on the tapered surface of which that first contact the adjacent wall of the hole being deformable somewhat to broaden the,

area of load bearing contact, and'said'plug also comprising a metal sealing plate supported by said refractory body and secured thereto and spacing the ingot to be poured therefrom and having its peripheral edge substantially in contact with the tapered wall of the hole immediately above the body portionof said plug, whereby said plate substantially seals said hole against fluid outflow and said refractory body substantially bears the weight of the ingot,

6. A mold plug having a truncated cone shaped body portion of porous burned clay, the exterior portion of which has a zone of increased porosity formed by mixing coal with. the clay prior to burning, and having a steel plate covering the circular face of the body portion-having the maximum diameter and fixedly secured to the body a portion with the edge of said plate lying substantially in'the surface of said cone, said plug being adapted to coact with -a similarly conical surface in the bottom hole of an ingot mold, the body of the plug in load bearing engagement therewith and the plate of the plug in fluid sealing relation thereto.

7. An ingot mold plug adapted to close a bottom tapered hole of an ingot mold comprising a frustro-conical non-metallic body portion. the conical surface of which substantially corresponds to at least aportion of the conical surface between the ends-of said bottom hole of said ingot mold, and said plug also comprising a metallic plate covering substantially the whole area of the upper circular surface of said non-metallic body said ingot mold but will not engage the name in load bearing relationship before the non-metallic body portion of said plug is firmly seated in said hole.

ARTHUR C. ES'I'EP. go 

